The present invention, in some embodiments thereof, relates to a method for facilitating a user selecting paths in an image and, more particularly, but not exclusively, to a method for facilitating the selection of particular blood vessels in a 3-D medical image showing one or more networks of blood vessels.
It is difficult to design methods that automatically segment blood vessels, and other connected networks in the body, with acceptably low rates of error. But having a human expert identify each blood vessel voxel by voxel would be impossibly time consuming. Methods that allow a human expert to interact effectively with a display of a medical image, to quickly identify particular blood vessels, could allow accurate segmentation to be achieved in a reasonable time.
The Vitrea Workstation made by Vital Images, and the Advantage Workstation made by General Electric, both include software that automatically finds major coronary arteries, as well as providing semi-automatic and manual tools for finding other arteries.
The Philips Brilliance Workstation includes a Comprehensive Cardiac Analysis application, which allows a user to hover a mouse on a 3D image, to indicate a particular blood vessel in a tree graph of coronary blood vessels, and to accept a suggestion for its path.
U.S. Pat. No. 7,369,691 to Kondo et al describes software that finds centerlines of blood vessels in a 3D image, which can be corrected by a user.
U.S. Pat. No. 6,501,848 to Carroll et al describes a computer reconstruction of a coronary vascular tree. A user can select two points on the image, and the computer then finds a path connecting them through the blood vessels, if one exists, and calculates such parameters as the length, average curvature, and tortuosity of the path.
U.S. Pat. No. 7,113,623 to Chen et al describes software that calculates a moving 3D coronal artery tree, over a cardiac cycle. User input is needed to identify points in the lumen of each artery initially.
U.S. Pat. No. 7,003,144 to Yim describes software that generates a graph of blood vessels from an angiogram. Optionally, the user identifies which points in the graph are distal endpoints of blood vessels, or in some cases the software can figure this out without help from the user.
US2008/0205728 to Quist describes software that generates a tree of pulmonary blood vessels from a CT image, in order to look for a pulmonary embolism, allowing a user to tell at a glance if a large part of the tree is missing.
US2008/0187199 to Gulsun et al describes software in which a user selects a seed that is near the beginning of a blood vessel, and the algorithm finds the centerline and tree structure of the blood vessel.